DEVELOPMENT PLANS FOR QUAKE-PRONE ISLAND SINK

Gerald D. Adams, San Francisco ExaminerCHICAGO TRIBUNE

Treasure Island, once viewed as a potential home for a world's fair to celebrate the new millennium, now is being eyed for less lofty pursuits-including San Francisco's version of the Mustang Ranch and a gambling casino.

The island is so vulnerable to a major earthquake that grandiose development plans for its post-Navy future such as Expo '99 or a permanent biotechnology complex are sinking faster than the island's mud fill.

The estimated $500 million-plus needed to shore up development against a potentially devastating earthquake has persuaded planners and developers to propose less altruistic but higher revenue-producing uses for the island.

Among the options considered at a recent all-day forum on the future of the island's 403 acres were: an adult theme park; a Mustang Ranch, billed by proponents as a way "to get prostitutes out of the Tenderloin"; an old-fashioned amusement park; a gaming casino; and a hotel with golf course, restaurants and conference center.

"We were looking for uses with high returns to pay for improvements," said Peter Laska, an architect who works for the city who took part in the forum.

It was Laska who suggested an adult theme park and a Mustang Ranch, a famed Nevada bordello.

The Navy is due to transfer ownership of Yerba Buena Island and Treasure Island to San Francisco in 1997.

The city's Redevelopment Agency is working with a citizens committee to develop plans for the property.

The proposals floated at the recent meeting were offered as concepts to investigate rather than concrete development plans.

Those attending the recent forum heard a series of grim pronouncements about the island's vulnerability.

City planner Alison Kendall and planning consultant Bonnie Fisher made these points:

- The island is a more dangerous place than San Francisco's Marina District, which suffered the city's greatest damage in the 7.1-intensity 1989 Loma Prieta temblor.

- In a 7-point earthquake on the Hayward Fault, the causeway which connects Treasure Island to the Bay Bridge would collapse, isolating the island from the mainland.

- Since its construction in 1936, Treasure Island already has sunk so far-from 13 feet above the bay to 9 feet-that some sections lie below the surface during high tide.

- Riprap dikes along the island's perimeter are so weak they need reinforcement. Estimated cost: $1,000 a foot for some 20,000 linear feet.

Bolstering the island and preparing it for development could cost as much as $577 million, according to a consultant's report by the Roma design group.

Add $60 million to $80 million for cleaning hazardous waste sites, said Saul Bloom, executive director of the Arms Control Research Center.

Geotechnical engineer Frank Rollo described the subterranean situation that makes the place rickety.